# CVE-2023-21839 — Oracle Corporation WebLogic Server **CISA KEV** > As of 2025-10-21, CVE-2023-21839 is a HIGH-severity vulnerability in Oracle Corporation WebLogic Server, CVSS v3.1 7.5, EPSS 99.9% (99.9th percentile). It is listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-05-01), with a US federal remediation deadline of 2023-05-22. Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2023-21839, most recently “Oracle WebLogic Server CVE-2024-21182 — Unauthenticated T3/IIOP Unspecified Vulnerability Added to CISA KEV on Active-Exploitation Evidence”. **Last updated:** 2025-10-21 ## What is CVE-2023-21839? Vulnerability in the Oracle WebLogic Server product of Oracle Fusion Middleware (component: Core). Supported versions that are affected are 12.2.1.3.0, 12.2.1.4.0 and 14.1.1.0.0. Easily exploitable vulnerability allows unauthenticated attacker with network access via T3, IIOP to compromise Oracle WebLogic Server. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Oracle WebLogic Server accessible data. CVSS 3.1 Base Score 7.5 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N). The record classifies CVE-2023-21839 under weakness class [CWE-306](https://intel.threadlinqs.com/cwe/CWE-306). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 1368 days ago. ## Severity and exploitation probability - **CVSS v3.1 base score:** 7.5 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`) - **EPSS (FIRST):** 99.9% probability of exploitation in the next 30 days, higher than 99.9% of all scored CVEs - **CISA KEV:** Listed since 2023-05-01, federal remediation deadline 2023-05-22 - **Threadlinqs priority:** 9/10 — CISA KEV-listed, which Threadlinqs floors at 9 - **Published:** 2023-01-17, last modified 2025-10-21 ## Is CVE-2023-21839 being exploited? CISA added CVE-2023-21839 to the Known Exploited Vulnerabilities catalog on 2023-05-01, which means the agency holds evidence of exploitation in the wild; US federal civilian agencies had to remediate it by 2023-05-22 under BOD 22-01. Weaponised exploit code for CVE-2023-21839 is publicly available. 9 public proof-of-concept repositories are tracked for this identifier. A ProjectDiscovery Nuclei detection template exists (`javascript/cves/2023/CVE-2023-21839.yaml`). It currently carries a trending score of 50 in the Threadlinqs vulnerability feed. - [DXask88MA/Weblogic-CVE-2023-21839](https://github.com/DXask88MA/Weblogic-CVE-2023-21839) (github) - [ASkyeye/CVE-2023-21839](https://github.com/ASkyeye/CVE-2023-21839) (github) - [dinosn/CVE-2024-20931](https://github.com/dinosn/CVE-2024-20931) (github) - [Firebasky/CVE-2023-21839](https://github.com/Firebasky/CVE-2023-21839) (github) - [houqe/POC_CVE-2023-21839](https://github.com/houqe/POC_CVE-2023-21839) (github) - [dinosn/CVE-2024-21182](https://github.com/dinosn/CVE-2024-21182) (github) - [Romanc9/Gui-poc-test](https://github.com/Romanc9/Gui-poc-test) (github) - [kw3h4/CVE-2023-21839-metasploit-scanner](https://github.com/kw3h4/CVE-2023-21839-metasploit-scanner) (github) ## Affected products and versions - [Oracle Corporation](https://intel.threadlinqs.com/vendors/oracle): WebLogic Server ## How to fix CVE-2023-21839 Because CVE-2023-21839 is KEV-listed, US federal civilian agencies were required to apply the vendor fix, or stop using the product, by 2023-05-22. No vendor patch reference has been recorded for CVE-2023-21839 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise. ## Threat activity tracking CVE-2023-21839 1 tracked threat in the Threadlinqs corpus references CVE-2023-21839, either in the campaign’s CVE list or as an indicator on the campaign record. - [Oracle WebLogic Server CVE-2024-21182 — Unauthenticated T3/IIOP Unspecified Vulnerability Added to CISA KEV on Active-Exploitation Evidence](https://intel.threadlinqs.com/threat/TL-2026-0649) — CRITICAL · 2026-06-01 ## Sources Enriched from CVE.org, FIRST EPSS, CISA KEV, GitHub Security Advisories, public proof-of-concept repositories, ProjectDiscovery Nuclei. Last verified by Threadlinqs on 2026-10-10. **Vendor advisory and patch** - [oracle.com — vendor advisory](https://www.oracle.com/security-alerts/cpujan2023.html) **Other references** - [packetstormsecurity.com](http://packetstormsecurity.com/files/172882/Oracle-Weblogic-PreAuth-Remote-Command-Execution.html) Canonical: https://intel.threadlinqs.com/cve/CVE-2023-21839 Full detection coverage and IOCs for threats exploiting CVE-2023-21839 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp